[RE-wrenches] weak voltage

[Chris Mason]

You should see a voltage drop across the connections if they are faulty.

On Mon, Oct 15, 2012 at 8:54 AM, mac Lewis <maclewis1 at gmail.com> wrote:

> Hmmm,
>
> This had factory installed bussing.  I will pull it off and clean it up.
>  Thanks.  I suppose that something like this be invisible to an Amp hr
> meter.
>
>
> On Sun, Oct 14, 2012 at 11:01 PM, William Miller <william at millersolar.com>wrote:
>
>> Mac:
>>
>> We had a similar problem with a large bank of IBE 2 volt cells.  The
>> batteries had to be removed the same day they were installed and then
>> reinstalled the next day.  They sat outside for one night.  The flags
>> acquired an invisible but insidious corrosion that caused problems getting
>> and keeping a charge.  Now we insist on cleaning each flag and eyelet no
>> more than 10 minutes prior to contact.
>>
>> William Miller
>>
>>
>>
>> At 09:41 PM 10/14/2012, you wrote:
>>
>>> Hi wrenches,
>>>
>>> About 2 months ago, we installed an off-grid Sunny Island System.  Here
>>> are the specs:
>>>
>>> 8.82 kW PV
>>> SunnyBoy 8000
>>> 2 x Sunny Island 5048 Inverters
>>> 2490 Ahr SolarOne HUP batteries at 48V
>>> 30 kW Cummins Propane Generator
>>>
>>> We are having an issue that I am having a hard time figuring out.  We
>>> are getting sagging battery voltage, and can't seem to keep the battery
>>> voltage and specific gravity where we want it.  In addition, I have
>>> equalized these batteries 4 times this past month, and the specific gravity
>>> gets to about 1.25-1.26 maximum.  I have slowly eased up the boost, absorb
>>> and equalize voltage setpoints, to try to get the battery a better charge,
>>> but it doesn't seem to help.  The Sunny Islands don't seem to have any
>>> issue getting these batteries up to the equalization voltage, or any of the
>>> other voltage set points.  I have checked for loose connections, all look
>>> good here.
>>>
>>> The SOC monitor on the Sunny Island master, calculates that we are
>>> staying between 70-95% SOC on a daily basis, and yet the battery voltage
>>> has dropped below readable level a few times(I believe this is below 41V).
>>>  I equalized at 62 V for 4 hours and had the same result of nonimpressive
>>> sepecific gravity and saggy voltage under small load.  After we leave from
>>> equalizing the batteries, things seem to be OK for a while and then we
>>> start having issues again.  We are tripping a 250A battery breaker, and
>>> getting low voltage errors on the SI, yet SOC looks good.
>>>
>>> Right now I have the set points programmed per SolarOnes advice as:
>>>
>>> Boost Voltage= 2.46 V/cell
>>> Full Charge Voltage = 2.46V/cell
>>> Equalize Voltage = 2.54V/cell
>>>
>>> Thanks in advance for any ideas that you may have.
>>>
>>>
>>>
>>> --
>>>
>>
>> ______________________________**_________________
>> List sponsored by Home Power magazine
>>
>> List Address: RE-wrenches at lists.re-wrenches.**org<RE-wrenches at lists.re-wrenches.org>
>>
>> Options & settings:
>> http://lists.re-wrenches.org/**options.cgi/re-wrenches-re-**wrenches.org<http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org>
>>
>> List-Archive: http://lists.re-wrenches.org/**pipermail/re-wrenches-re-**
>> wrenches.org<http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org>
>>
>> List rules & etiquette:
>> www.re-wrenches.org/etiquette.**htm<http://www.re-wrenches.org/etiquette.htm>
>>
>> Check out participant bios:
>> www.members.re-wrenches.org
>>
>>
>
>
> --
>
>
>
> Mac Lewis
>
> *
>
> "Yo solo sé que no sé nada." -Sócrates
> *
>
> _______________________________________________
> List sponsored by Home Power magazine
>
> List Address: RE-wrenches at lists.re-wrenches.org
>
> Options & settings:
> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
>
> List-Archive:
> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
>
> List rules & etiquette:
> www.re-wrenches.org/etiquette.htm
>
> Check out participant bios:
> www.members.re-wrenches.org
>
>
>


-- 
Chris Mason
President, Comet Systems Ltd
www.cometenergysystems.com
Cell: 264.235.5670
Skype: netconcepts
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20121015/36dd57bd/attachment-0003.html>